Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2022

Accounting Policies [Abstract]

Summary of Commission Revenue by Fee Type

The following table presents commission revenue by fee type:

	Year Ended December 31,
	2022		2021		2020
	(In thousands)
Commission revenue by fee type
Variable transaction fees
Disclosed trading	$	321,603	$	333,712	$	343,427
Open Trading - matched principal trading		175,440		155,465		170,537
U.S. government bonds - matched principal trading		16,978		12,400		12,372
Total variable transaction fees		514,021		501,577		526,337
Distribution fees and unused minimum fees		127,162		119,431		108,108
Total commissions	$	641,183	$	621,008	$	634,445

Summary of Information Services Revenue by Timing of Recognition

The following table presents information services revenue by timing of recognition:

	Year Ended December 31,
	2022		2021		2020
	(In thousands)
Information services revenue by timing of recognition
Services transferred over time	$	38,452	$	37,341	$	32,425
Services transferred at a point in time		862		834		1,916
Total information services revenues	$	39,314	$	38,175	$	34,341

Summary of Post-Trade Services Revenue by Timing of Recognition

The following table presents post-trade services revenue by timing of recognition:

	Year Ended December 31,
	2022		2021		2020
	(In thousands)
Post-trade services revenue by timing of recognition
Services transferred over time	$	36,835	$	38,850	$	19,158
Services transferred at a point in time		42		72		302
Total post-trade services revenues	$	36,877	$	38,922	$	19,460

Summary of Revenue Recognized from Contract Liabilities and Remaining Balance

The revenue recognized from contract liabilities and the remaining balance is shown below:

	December 31, 2021		Payments received in advance of services to be performed		Revenue recognized for services performed during the period			Foreign Currency Translation			December 31, 2022
	(In thousands)
Information services	$	3,528	$	10,821	$	(11,228	)	$	—		$	3,121
Post-trade services		720		16,099		(15,876	)		(74	)		869
Total deferred revenue	$	4,248	$	26,920	$	(27,104	)	$	(74	)	$	3,990